Your error here is how you are qualifying something as a 'mistake.' All of your above examples do is illustrate how it is a mistake in your opinion. You thinking it is a bad idea does not actually make it a mistake. A factual mistake would be something like an SE employee forgetting a 0 when he entered the price into Steam or lousing up the math when working out the conversion rate. I certainly agree with you that how they handled the increase was a big mistake but those are, again, only our opinions.
As to your last two questions, it depends what you mean by "this," it was rather unclear if you meant the original lower pricing or the price change. If you were talking about the former- This is objectively false. The lower price allowed them to sell the game to more people in these regions, which is the entire point of regional pricing and is why it is such a common practice among video game developers. More sales, even at a lower cost, meant an increased profit for SE.
Only time will tell. They are going to lose subscribers from this, that is a fact. I would think that they had someone crunching the numbers to work out if the increased revenue from those who stay will make up for the losses before they gave this the green light, but in the end those are only estimates. We'll have to see if they end up losing or making money from this.
As a member of the BR/RU community it most certainly does reflect upon me when you choose to cast an erroneous, inflammatory blanket statement over us, and you can bet your buttons I am going to call out you or anyone else who attempts to do so.
(In case it's not clear, 'erroneous and inflammatory' in the sense that you painted the reasons for our outrage in the worst possible light, intentionally misrepresenting myself and the many, many people who stated point-blank that our issue was with the manner and not the action itself.)